This invention relates to a non-penetrating projectile which may be adapted for use as a medication delivery system, for example for delivering a tranquillising substance, drug, vaccine, medication, identification means or tracking device to an animal or to any other target. The system may also be used to take a sample of tissue. Such projectiles are commonly referred to as tranquilliser darts and their primary purpose is to provide means for remotely delivering and injecting a tranquillising fluid or medication into an animal without causing undue harm or stress.
This invention also relates to a projectile which can be adapted for use as a non-lethal projectile commonly referred to as a xe2x80x9cbaton roundxe2x80x9d or xe2x80x9crubber bulletxe2x80x9d.
With reference to the first mentioned us, there has long been a need to capture, study, relocate or medicate animals and various means are used. The most commonly used method being by means of some form of adapted syringe containing a tranquilliser which is propelled and injected on impact into the animal. These tranquilliser dart devices have serious disadvantages primarily being lack of range and accuracy due to poor ballistic properties and the highly parabolic trajectory making range estimation critical. As a projectile the devices are inherently unstable due to length and weight and cannot be spin stabilised to any useful degree due to the low velocity which is required to avoid deep penetration which is a major factor. The known devices are also complex to assemble and load often with highly toxic drugs and are heavy in relation to the delivered payload.
It is one object of this invention to provide a tranquilliser or other medication delivery system using a projectile, being preferably spin stabilised having improved range and accuracy and of an inherently stable ballistic shape, being an improvement and a modification of the projectile described and claimed in WO 00/71967A1 and GB2350414 A1.
Another alternative object is to provide a projectile which has limited, controlled or no penetration into a target.
Yet a further alternative object is to provide a projectile which itself does not include an explosive or gas producing charge.
A further alternative object of this invention to provide a non-lethal projectile which may be fired with accuracy at a soft target directly and even at close ranges and which is designed not to penetrate to any significant extent and which should only cause minimal injury to the limbs or torso.
Another alternative object is to provide a projectile which is capable of marking the target for subsequent identification.
In accordance with a first aspect of this invention there is provided a projectile including means to effectively retard the velocity of the projectile on impact with a target wherein the velocity is retarded in such a way as to prevent excess injury or penetration by deployment of means, following impact with a target, which rapidly expands to produce a large increase in the area at the nose of the projectile to spread the kinetic energy over a large area, characterised in that said expansion of said means is effected using a pressurised gaseous medium carried in the projectile.
Preferably the velocity retarding means comprises an inflatable membrane which is subject to the pressurised medium through means actuated on impact with a target, for example by a impact sensor or by means of a proximity sensing means, or by physical displacement actuating a valve device, the membrane being inflated using said pressure, preferably being gas pressure, stored in the projectile and preferably derived from the propulsive charge gases occurring on firing the projectile from a weapon.
In accordance with a second aspect of this invention there is also provided a projectile with means to effectively retard the velocity of the projectile on impact with the target for the purpose of preventing penetration, wherein the velocity retarding means comprises an inflatable membrane actuated on or close to impact, for example by a impact sensor or by means of a proximity sensing means, the membrane being inflated using gas pressure stored in the projectile, said pressure being preferably derived from the propulsive charge gases occurring on firing from a weapon.
In accordance with a third aspect of this invention there is provided a projectile comprising a rear canister part and a forward nose part connected therewith, the canister part containing or adapted to contain a pressure gas, the forward end of the canister part having a valve means, the nose part comprising a profiled impact deformable material with a portion to act on and open the valve following impact, the nose part having a membrane around the deformable material, the membrane being inflated on release of the pressure gas through opening of the valve.
The velocity is retarded in such a way as to prevent excess injury or penetration and may be achieved by means which rapidly produces a large increase in area at the nose of the projectile thus spreading and dissipating the kinetic energy over a large area.
Preferably the projectile is adapted to be fired from a barrel weapon which may be rifled to impart spin. The projectile may be of sub-calibre design using a discarding sabot and be fired in a barrel having progressive rifled pitch to attain a velocity greater than 500 m/s.
In one preferred construction the projectile has a body with a cavity containing a payload, such as a marker fluid or dye and an ogival nose.
The velocity retarding means comprises a means to significantly increase the area of the projectile nose portion on initial impact by inflation to produce unfurling or unfolding, or by expansion through stretching or by a combination of both.
In one construction the velocity retarding means comprises an inflatable membrane which opens up or expands through gas pressure and actuated by a sensor on initial impact or using a proximity sensing means.
In an alternative the membrane is pre-pressurised and expands following discarding of an overlaying covering forming a constraining means.
The membrane may be inflated through a detonator and gas producing explosive charge or through use of stored gas pressure. This charge or stored pressure may also serve for the purpose of dissipating the marker by driving a piston in the containing cavity.
The membrane can be located in the nose of the projectile comprising a readily broken, fragmenting, unfurling or deployable cap, The membrane may be in the form of a bag attached to and around a forward end of the projectile nose thus preventing penetration beyond a predetermined depth.
The nose part of the projectile may include a solid foam-like or gel-like substance forming an energy absorbing material which spreads on impact. More specifically the gel may comprise a nano-porous open cell foam of the kind known by the trade mark Aerogel.